JPH11257509A - Directional control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a directional control valve from a small number of constituent parts and comparatively simply assemble the directional control valve. SOLUTION: In this directional control valve 10 which is equipped with a supply connecting part P, a return connecting part R and motor connecting parts A, B and in which these connecting parts are opened in an operation chamber 20 in the notch 14 of a casing 12 and controlled by a slider 24, a journalled ring zone guiding motionally the slider 24 is a metallic dense sleeve 18, the sleeve 18 is pressure-fitted in the notch 14, the piston section 26 of the slider 24 has at least one seal element 30 arranged around the piston section 26, and this seal element 30 is cooporated with the inner wall of the sleeve 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a directional control valve comprising a casing, the casing being closed at both ends by closing members, at least one supply connection, at least one return. A connection and at least one motor connection, these connections opening into a closed working chamber with respect to each other and the outside of the casing, and having a slider, wherein the slider is notched Having at least one piston section for control of the flow of pressure medium through the working chamber, movably guided by axially spaced bearing rings therein. About things.

[0002]

2. Description of the Related Art A directional control valve of the above-mentioned type is known, for example, from DE-A-34 27 127 A1. The valve casing of the directional control valve has one main hole (Hauptbohrung) that is stepped a plurality of times. A piston slider is arranged in the main bore for longitudinal movement. Functional elements are provided for guiding the piston slider and for sealing the working chamber controlled by the piston slider. The functional element has a casing in the form of a cage which is open on one side and has a sealing element in which the casing is fitted. A sealing element cooperates with the peripheral surface of the piston slider. The fixed fixation of the functional element in the valve housing is achieved by a light interference fit between the main bore and the casing of the sealing element (leichte Pressverbindu
ng), and subsequent adhesion. In this case, therefore, errors in the metering of the adhesive amount can lead to insufficient fixing or overflow of the adhesive onto the sealing element. Furthermore, bonding in the manufacture of directional control valves requires additional costs. Openings and passages are provided in the valve casing for bonding, and such openings and passages increase the manufacturing costs of the valve casing. Furthermore, the multi-part construction of the functional element increases the assembly costs.

[0003] European Patent Publication No. 0472910A1
Another type of directional control valve is disclosed in the publication, the casing of which is formed in a cup shape and has a cylindrical slider bore. Functional elements for guiding and sealing the slider are pressed into the housing. To ensure the positioning accuracy of the slider, the press-fitting process is performed while monitoring the distance. Therefore, the assembly cost increases. During the press-fitting process of the functional element directed to the innermost, that is to say the bottom of the housing, damage to the housing wall can occur due to the relatively long press-in distance. As a result, the interference fit of subsequent functional elements, in particular the last press-fitted functional element, is not precisely defined.

[0004]

It is an object of the present invention to obviate the aforementioned disadvantages of the prior art.

[0005]

In order to solve the above-mentioned problem, according to the construction of the present invention, the bearing ring is made of a dense metal sleeve.
(massive, metallische Huelse), wherein the sleeve is einpressen in the notch, and at least one piston section of the slider has at least one sealing element arranged around it, A sealing element cooperates with the inner wall of the sleeve.

[0006]

With the arrangement according to the invention, the directional control valve is formed from a small number of components and is relatively easy to assemble. Such components are inexpensive to manufacture without spanlos and are relatively easy to assemble.

The guidance of the slider is effected by means of a dense metal sleeve, which is pressed into the casing to a stop in an automatable work process. In this case, the risk of damage to the wall of the slider hole does not occur based on the stepped inner diameter of the slider hole. The sleeve has a peripheral sealing edge, so that a separate sealing element between the casing and the sleeve is not required. This saves part and assembly costs and reduces the space required for the directional control valve. The edge of the sleeve defining the pressure medium flow of the directional control valve (Kante) is relatively easily adaptable in terms of fluid technology, so that the directional control valve has a relatively short construction and a relatively large pressure medium. Allow flow rate. Furthermore, the directional control valve according to the invention has a high flexibility in the arrangement of the connection. Advantageous configurations of the invention are set out in the dependent claims.

[0008]

FIG. 1 shows a directional control valve (Wegeventil in 5 / 2-Bauweise) 10 of a 5/2 construction as an example, which directional control valve is particularly pneumatically operated.
che Anwendung), but not limited to this.

The directional control valve 10 is an integral casing 1
2, the casing being provided with a penetrating longitudinal notch 14 having a circular cross section. The inside diameter of the longitudinal cutout 14 decreases stepwise from the outside to the inside. The section 14a with the largest inner diameter is located in the region of the opening on the side of the longitudinal cutout 14, whereas the section 14c with the smallest inside diameter is located in the center of the casing 12.

The transition between the individual sections 14a to 14c is formed at right angles for the formation of the support shoulder 16. A sleeve 18 is in contact with the support shoulder 16 from side to end. The outer diameter of the sleeve 18 is divided into sections 14a to 1
For the corresponding inner diameter of 4c, it is provided that an interference fit (Pressverbindung) is created between the sleeve and the wall of the longitudinal cutout 14. The sleeve 18 is fixedly fixed in the casing 12 by such an interference fit. As the sleeve 18, a ring-shaped dense component (massiver ringfoermi) having the same inner diameter as each other is used.
ger Bauteil), and the component is a directional control valve 1
At the time of assembling 0, it is inserted into the casing 12 through the opening of the longitudinal cutout 14 from both sides.

The sleeves 18 are arranged at an axial distance from one another based on their positioning on the support shoulders 16, whereby the working chamber (Arbei
tskammer) 20 is formed. The working chamber 20 is connected to a supply connection P, a return connection R, or motor connections A, B via a passage on the casing side. In the embodiment, the supply connection P is a central connection. Motor connection parts A and B are arranged on both sides of the supply connection part P. An outermost connection portion of the casing 12 communicates with the return passage R.

In the embodiment, all the connection parts P, A,
B and R are arranged on one common side of the casing 12. An arrangement on the opposite side of the casing 12 is likewise conceivable.

A single slider hole (Schie) in which the same inner diameter of the sleeve 18 is interrupted a plurality of times by the working chamber 20.
berbohrung) 22. A slider 24 is guided in the slider hole 22 such that the slider 24 can move in the vertical direction for controlling the pressure medium flow by the direction control valve 10. The slider 24 extends over the entire length of the slider hole 22,
It has a number of piston sections 26 corresponding to the number of press-fit sleeves 18. The piston sections 26 are tightly connected to one another (miteinander fest verbinden) via a neck-shaped connecting section 28. The piston section 26 having a larger outer diameter than the coupling section 28 has a sealing element (Diechte
lement) 30. Instantaneous position of slider 24
In connection with (momentane Stellung), the pressure medium connection between two adjacent working chambers 20 is opened or closed via the piston section 26. The sealing element 30 arranged in the piston section 26 can be fitted as a separate part (Einzelteil) on the piston section 26 of the slider 24 or can be optionally vulcanized into the piston section. This is particularly advantageous for sliders 24 made of plastic.

In order to avoid inadvertent leakage of the pressure medium between two adjacent working chambers 20 through the gap between the peripheral wall of the sleeve 18 and the inner wall of the longitudinal notch 14, Reference numeral 18 denotes an annular seal edge (Dichtkante) 3 on the outer periphery (Aussenumfang) as shown in FIG.
2 is provided. The sealing edge 32 is wedge-shaped inclining in the direction opposite to the direction of press-fitting of the sleeve 18 and cuts into the wall of the longitudinal recess 14 during the press-fitting process.
This allows a reliable seal of the sleeve 18 and thus an additional fixing of the position.

The actuation of the slider 24 takes place in the exemplary embodiment via a working piston 34, which is arranged here at both ends of the casing 12. The working piston 3 is movably guided into the inner chamber of the cup-shaped closing member 36. The working piston 34 has a ring-shaped lip seal 38, and seals a pressure chamber 40 (not shown) that can be loaded with a pressure medium. Closure member 36
Is pressed tightly on the casing 12 and closes the lateral opening of the longitudinal recess 14.

Modifications of the above-described embodiment are possible without departing from the spirit of the invention. In this context,
The casing 12 can be manufactured particularly economically and without injection machining by means of injection molding technology. For this, plastic is particularly suitable as material, but aluminum can also be used. In both cases, the material of the sleeve 18 may have a higher modulus of elasticity (Elastizitaetsmodul) than the material of the casing 12 for a secure interference fit within the casing 12. Therefore, in the case of the casing 12 made of plastic,
The use of aluminum is suitable for the sleeve 18; in the case of the casing 12 made of aluminum, a sleeve 18 made of steel is used.

The longitudinal cutouts 14 are stepwise reduced from one end face of the casing 12 to the other end face, instead of having the diameter gradually decrease inward from both end faces of the casing 12 as already described. It is also conceivable to configure so as to reduce the size sequentially. In this case, the largest diameter section 14a is located on one end face of the casing 12, and the smallest diameter section 14c is located on the other end face of the casing.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a directional control valve according to the present invention.

FIG. 2 is an enlarged view of a portion denoted by reference numeral Z in FIG.

[Explanation of symbols]

10 directional control valve, 12 casing, 14
Longitudinal notch, 16 support shoulders, 18 sleeve, 20 working chamber, 22 slider hole, 2
4 slider, 26 piston section, 28 coupling section, 30 seal element, 32 seal edge, 34 working piston, A, B motor connection,
P supply connection, R return connection

 ──────────────────────────────────────────────────の Continuation of the front page (72) Inventor Radu Gimpu-Mundinger Germany Leonberg Beth-Wenstrasse 6

Claims (10)

[Claims] 1. A directional control valve (10) comprising a casing (12), the casing being closed at both ends by closure members (36),
It has one supply connection (P), at least one return connection (R) and at least one motor connection (A, B), which are connected to each other and to the outside of the casing (12). An open working space (20) and a slide (24) are provided in the closed working chamber (20), the slides being arranged in the notch (14) in axially spaced bearing rings (18). ) And having at least one piston section (26) for controlling the flow of pressure medium through the working chamber (20), the bearing ring is made of metal. A tight sleeve (18), which is pressed into the notch (14), wherein at least one piston section (26) of the slider (24) is arranged around at least one sealing element Has 30), characterized in that said sealing element is in cooperation with the inner wall of the sleeve (18), the directional control valve. 2. A notch (14) is stepped through the inner diameter several times to form a shoulder (16), and a sleeve (1) is provided.
8) is a shoulder (1) of a notch (14) at one end face.
2. The directional control valve according to claim 1, which is in contact with (6). 3. The sleeve (18) has a different outer diameter and has at least one peripheral sealing edge (3).
The directional control valve according to claim 1 or 2, further comprising (2). 4. The directional control valve according to claim 1, wherein the housing (12) is formed in one piece and is manufactured non-cuttingly. 5. The directional control valve according to claim 4, wherein the casing (12) can be manufactured by injection molding technology and is made of aluminum or plastic. 6. The directional control valve according to claim 1, wherein the material of the sleeve (18) has a higher elastic modulus than the material of the casing (12). 7. The directional control valve (10) has five connections (P, R, A, B) for supply, return and motor, said connections being common to the casing (12). 7. A directional control valve according to claim 1, which is arranged on one side. 8. The slider according to claim 1, wherein the slider is formed as a hollow or solid slider made of aluminum or brass, and the sealing element is arranged on the slider. The directional control valve according to claim 1. 9. The directional control valve according to claim 1, wherein the directional control valve is a 5/2 directional control valve. 10. The notch (14) has a casing (12).
Has the largest diameter on both end faces and has a notch (1
3. The directional control valve according to claim 2, wherein said directional control valve has a minimum diameter at the center of said step (4).